Removing Concrete Ridge and Ground Protection on Ground Floor

Hi,

I have done a few projects (replace windows and doors, wiring, plumbing) but I could use some helpful feedback on this project. I would like to replace a door that is on the first floor of a slab house (Long Island, New York) with an Anderson sliding door.

I know to put a support wall inside the house wider than the header I am installing to prevent any damage or second floor sagging. I have already installed an Anderson sliding door so I am not concerned about that part of the project.

What I would like advice on is two things:

I need to remove a concrete ridge (about 8 inches high and 8 inches wide) that is 36” on one side of the opening and 18” on the other side (Concrete Ridge Outside View dyi.jpg). A close-up is in the photo labeled “concrete ridge dyi.jpg.” This is on either side of the existing door that I am replacing with a larger patio sliding door.

_____ Is there an easy/best way to knock down/remove this ridge and get the remaining area below it level and smooth?

______What protection do I need to place under the Anderson frame to protect it from the ground and weathering (or do I place treated wood there first)? I believe I read somewhere of a plastic that should be laid down to protect the wood.

I also am working with an exterior factor of a steel detached balcony. I have measured the required rough opening and the door will fit. I am going to install an Anderson 400 series Frenchwood gliding patio door (PWG6068 – rough opening 72” by 80”). I have 82.5” from the outside concrete floor to the I-beam. I believe I will have to put the door frame in top first to fit under the existing shingles and behind the I-beam (Door and Ibeam dyi.jpg). The red vertical marks on the shingles in this photo indicate the rough opening of the sliding door.